The following relates generally to wireless communication, and more specifically to techniques for cross-carrier scheduling using multiple transmission time interval durations.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems, (e.g., a Long Term Evolution (LTE) system, or a New Radio (NR) system). A wireless multiple-access communications system may include a number of base stations or access network nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).
In a LTE or LTE-Advanced (LTE-A) network, a set of one or more base stations may define an eNodeB (eNB). In other examples (e.g., in a NR or 5G network), a wireless multiple access communication system may include a number of smart radio heads (RHs) in communication with a number of access node controllers (ANCs), where a set of one or more RHs, in communication with an ANC, defines a base station (e.g., an eNB or gNB). A base station may communicate with a set of UEs on downlink (DL) channels (e.g., for transmissions from a base station to a UE) and uplink (UL) channels (e.g., for transmissions from a UE to a base station).
A base station in some LTE or NR deployments may transmit downlink transmissions to one or more UEs, and the one or more UEs may transmit uplink transmissions back to the base station. In some cases, a base station may transmit to one or more UEs using a transmission time interval (TTI) that is reduced in length relative to other TTIs that may be configured. Such a TTI may be referred to as a shortened TTI (sTTI) and users receiving an sTTI may be using a low latency service provided by the LTE or NR network. In some cases, multiple component carriers (CCs) may be configured for communications between a base station and one or more UEs. Efficient scheduling of sTTI resources across multiple CCs for one or more UEs may be desirable in order to preserve the relatively few sTTI resources that are available for low latency communications.